update lab2

Lab 1/Lab_1.java

@@ -1,39 +0,0 @@
-import java.util.Scanner;
-
-public class Lab_1 {
-    public static void main(String[] args) {
-        int n, m, a, b;
-        float s = 0;
-
-        Scanner input = new Scanner(System.in);
-        
-        System.out.print("Enter n: ");
-        n = input.nextInt();
-
-        System.out.print("Enter m: ");
-        m = input.nextInt();
-
-        do {
-            System.out.print("Enter a (can't be above n): ");
-            a = input.nextInt();
-        } while (a > n);
-
-        do {
-            System.out.print("Enter b (can't be above m): ");
-            b = input.nextInt();
-        } while (b > m);
-
-        if ((a <= 0) && (n >= 0)) {
-            System.out.println("Error, division by zero, shutting down!");
-            System.exit(1);
-        }
-
-        for (int i = a; i < n; i++) {
-            for (int j = b; j < m; j++) {
-                s += i * j / i;
-            }
-        }
-
-        System.out.println("S = " + s);
-    }
-}

src/Lab2.java

@@ -1,13 +1,36 @@
 public class Lab2 {
     public static void main(String[] args) {
-        int[] array = {1, 2, 3};
-        /*for (int i = 0; i < array.length; i++) {
+        final int A = 2;
+        final int[][] MATRIX_B = {
+                {1, 202, 1, 1, 202, 3, 1, 202, 3,},
+                {1, 202, 1, 1, 202, 3, 1, 202, 3,},
+                {1, 1,   3, 1, 202, 3, 1, 202, 3,},
+//                {4, 5, 6,},
+        };
+
+        int[][] MATRIX_C = multiplication(A, MATRIX_B);
+
+        print(MATRIX_C);
+
+        System.out.println("Sum of smallest elements in every column: " + sumOfSmallestElementsInEveryColumn(MATRIX_C));
+
+        /*int[] array = {1, 2, 3};
+        int[] array2 = new int[3];
+        Object[] array3 = new String[3];
+        System.out.println(array3[0]); //nothing, trash from the memory, null || null
+        System.out.println(array2[0]); //nothing, trash from the memory, null || 0
+        System.out.println(array[0]); // || 1
+
+        int[][] matrix2 = new int[2][3];
+        matrix2[0] = new int[2];
+        matrix2[1] = new int[1];
+        for (int i = 0; i < array.length; i++) {
             if (i % 2 == 0) {
                 System.out.println("!" + array[i]);
             } else {
                 System.out.println("?" + array[i]);
             }
-        }*/
+        }
 
         for (int i = 0; i < array.length; i+=2) {
             System.out.println("!" + array[i]);
@@ -22,5 +45,58 @@ public class Lab2 {
                 {1, 2},
                 {3}
         };
+
+//        C=a×B, a - const
+
+
+//        final int[][] MATRIX_C = int;
+
+
+        MATRIX_B[0][0] = 2;
+        MATRIX_B[0] = new int[]{1, 2};
+        System.out.println(MATRIX_B[0][0]);
+        MATRIX_B = new int[][]{
+                {1, 2},
+                {3}
+        };*/
+    }
+
+    private static int sumOfSmallestElementsInEveryColumn(final int[][] MATRIX_C) {
+//        todo check different length of rows
+//        todo try to change i and j
+//        todo check repetition of minimal elements
+        int sum = 0;
+        for (int i = 0; i < MATRIX_C[0].length; i++) {
+            int tmpSmallest = MATRIX_C[0][i];
+            for (int j = 1; j < MATRIX_C.length; j++) {
+                if (MATRIX_C[j][i] < tmpSmallest) {
+                    tmpSmallest = MATRIX_C[j][i];
+                }
+            }
+            sum += tmpSmallest;
+        }
+        return sum;
+    }
+
+    private static void print(final int[][] MATRIX_C) {
+        for (int i = 0; i < MATRIX_C.length; i++) {
+            for (int j = 0; j < MATRIX_C[i].length; j++) {
+//                System.out.print(MATRIX_C[i][j] + "\t");//printf("%4d",
+                System.out.printf("%4d ", MATRIX_C[i][j]);//printf("%4d",
+            }
+            System.out.println();
+        }
+    }
+
+    private static int[][] multiplication(int A, final int[][] MATRIX_B) {
+        final int[][] MATRIX_C = new int[MATRIX_B.length][/*MATRIX_B[0].length*/]; // todo !!!DANGER different lengths of rows
+//        final int[][] MATRIX_C = MATRIX_B;
+        for (int i = 0; i < MATRIX_B.length; i++) {
+            MATRIX_C[i] = new int[MATRIX_B[i].length];
+            for (int j = 0; j < MATRIX_B[i].length; j++) {
+                MATRIX_C[i][j] = MATRIX_B[i][j] * A;
+            }
+        }
+        return MATRIX_C;
     }
 }